Integrated chip package structure using ceramic substrate and method of manufacturing the same

ABSTRACT

An integrated chip package structure and method of manufacturing the same is by adhering dies on a ceramic substrate and forming a thin-film circuit layer on top of the dies and the ceramic substrate. Wherein the thin-film circuit layer has an external circuitry, which is electrically connected to the metal pads of the dies, that extends to a region outside the active surface of the dies for fanning out the metal pads of the dies. Furthermore, a plurality of active devices and an internal circuitry is located on the active surface of the dies. Signal for the active devices are transmitted through the internal circuitry to the external circuitry and from the external circuitry through the internal circuitry back to other active devices. Moreover, the chip package structure allows multiple dies with different functions to be packaged into an integrated package and electrically connecting the dies by the external circuitry.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan applicationserial no. 90133092, filed Dec. 31, 2001.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an integrated chip package structureand method of manufacture the same. More particularly, the presentinvention relates to an integrated chip package structure and method ofmanufacture the same using ceramic substrate.

2. Description of Related Art

In the recent years, the development of advanced technology is on thecutting edge. As a result, high-technology electronics manufacturingindustries launch more feature-packed and humanized electronic products.These new products that hit the showroom are lighter, thinner, andsmaller in design. In the manufacturing of these electronic products,the key component has to be the integrated circuit (IC) chip inside anyelectronic product.

The operability, performance, and life of an IC chip are greatlyaffected by its circuit design, wafer manufacturing, and chip packaging.For this present invention, the focus will be on chip packagingtechnique. Since the features and speed of IC chips are increasingrapidly, the need for increasing the conductivity of the circuitry isnecessary so that the signal delay and attenuation of the dies to theexternal circuitry are reduced. A chip package that allows good thermaldissipation and protection of the IC chips with a small overalldimension of the package is also necessary for higher performance chips.These are the goals to be achieved in chip packaging.

There are a vast variety of existing chip package techniques such asball grid array (BGA), wire bonding, flip chip, etc. . . . for mountinga die on a substrate via the bonding points on both the die and thesubstrate. The inner traces helps to fan out the bonding points on thebottom of the substrate. The solder balls are separately planted on thebonding points for acting as an interface for the die to electricallyconnect to the external circuitry. Similarly, pin grid array (PGA) isvery much like BGA, which replaces the balls with pins on the substrateand PGA also acts an interface for the die to electrically connect tothe external circuitry.

Both BGA and PGA packages require wiring or flip chip for mounting thedie on the substrate. The inner traces in the substrate fan out thebonding points on the substrate, and electrical connection to theexternal circuitry is carried out by the solder balls or pins on thebonding points. As a result, this method fails to reduce the distance ofthe signal transmission path but in fact increase the signal pathdistance. This will increase signal delay and attenuation and decreasethe performance of the chip.

Wafer level chip scale package (WLCSP) has an advantage of being able toprint the redistribution circuit directly on the die by using theperipheral area of the die as the bonding points. It is achieved byredistributing an area array on the surface of the die, which can fullyutilize the entire area of the die. The bonding points are located onthe redistribution circuit by forming flip chip bumps so the bottom sideof the die connects directly to the printed circuit board (PCB) withmicro-spaced bonding points.

Although WLCSP can greatly reduce the signal path distance, it is stillvery difficult to accommodate all the bonding points on the die surfaceas the integration of die and internal devices gets higher. The pincount on the die increases as integration gets higher so theredistribution of pins in an area array is difficult to achieve. Even ifthe redistribution of pins is successful, the distance between pins willbe too small to meet the pitch of a printed circuit board (PCB).

SUMMARY OF THE INVENTION

Therefore the present invention provides an integrated chip packagestructure and method of manufacturing the same that uses the originalbonding points of the die and connect them to an external circuitry of athin-film circuit layer to achieve redistribution. The spacing betweenthe redistributed bonding points matches the pitch of a PCB.

In order to achieve the above object, the present invention presents anintegrated chip package structure and method of manufacturing the sameby adhering the backside of a die to a ceramic substrate, wherein theactive surface of the die has a plurality of metal pads. A thin-filmcircuit layer is formed on top of the die and the ceramic substrate,where the thin-film circuit layer has an external circuitry that iselectrically connected to the metal pads of the die. The externalcircuitry extends to a region that is outside the active area of thedies and has a plurality of bonding pads located on the surface layer ofthe thin-film layer circuit. The active surface of the die has aninternal circuitry and a plurality of active devices, where signals canbe transmitted from one active device to the external circuitry via theinternal circuitry, then from the external circuitry back to anotheractive device via the internal circuitry. Furthermore, the ceramicsubstrate has at least one inwardly protruded area so the backside ofthe die can be adhered inside the inwardly protruded area and exposingthe active surface of the die. Wherein the ceramic substrate is composedof a ceramic layer and a heat conducting material formed overlapping andthe inwardly protruded areas are formed by overlapping the ceramicsubstrate with openings on the heat conducting layer. Furthermore, thepresent chip package structure allows multiple dies with same ordifferent functions to be packaged into one integrated chip package andpermits electrically connection between the dies by the externalcircuitry.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary, and are intended toprovide further explanation of the invention as claimed.

BRIEF DESCRIPTIOIN OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention. In the drawings,

FIGS. 1A to 1I are schematic diagrams showing the sectional view of thestructure of the first embodiment of the present invention.

FIGS. 2A to 2C are schematic diagrams showing the sectional view of thestructure of the second embodiment of the present invention.

FIGS. 2D to 2E are schematic diagrams showing the section view of theformation of inwardly protruded areas in the organic substrate of thestructure of the second embodiment of the present invention.

FIGS. 3A to 3C are schematic diagrams showing the sectional view of thestructure of the third embodiment of the present invention.

FIGS. 4A to 4I are schematic diagrams showing the sectional view of thestructure of the forth embodiment of the present invention.

FIGS. 5A to 5E are schematic diagrams showing the sectional view of thestructure of the fifth embodiment of the present invention.

FIG. 6 is a schematic diagram showing the section view of the chippackage structure of a preferred embodiment of the present inventionwith one die.

FIG. 7 is a schematic diagram showing the section view of the chippackage structure of a preferred embodiment of the present inventionwith a plurality of dies.

FIG. 8 is a magnified diagram showing the sectional view of the chippackage structure of a preferred embodiment of the present invention.

FIGS. 9A, 9B are schematic diagrams of the top and side viewrespectively of the patterned wiring layer of the thin-film circuitlayer with a passive device.

FIG. 10A is a schematic diagram of the formation of a passive device bya single layer of patterned wiring layer of the thin-film circuit layer.

FIG. 10B is a schematic diagram of the formation of a passive device bya double layer of patterned wiring layer of the thin-film circuit layer.

FIG. 11A is a schematic diagram of the formation of a passive device bya single layer of patterned wiring layer of the thin-film circuit layer.

FIG. 11B is a schematic diagram of the formation of a passive device bya double layer of patterned wiring layer of the thin-film circuit layer.

FIG. 11C is a schematic diagram of the formation of a passive device bya double layer of patterned wiring layer of the thin-film circuit layer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIEMENTS

Please refer to FIG. 1A, a ceramic substrate 110 with a surface 112usually of aluminum oxide material or other ceramic material isprovided. A plurality of dies 120 having an active surface 122 and abackside 124 is also provided, where the active devices are formed onactive surface 122 of the dies. Furthermore, dies 120 have a pluralityof metal pads 126 located on active surface 122 of dies 120 acting asthe output terminal of dies 120 to transmit signals to the externalcircuitry. Backside 124 of dies 120 is adhered to surface 112 of ceramicsubstrate 110 by a conductive paste or adhesive tape. Therefore, activesurface 122 of dies 120 is facing upwards along surface 112 of ceramicsubstrate 110.

Please refer to FIG. 1B, when adhering die 120 to ceramic substrate 110,a filling layer 130 can be formed on top of surface 112 of ceramicsubstrate 100 surrounding the peripheral of dies 120 to fill the gapbetween dies 120. The height of filling layer 130 should beapproximately equal to the height of active surface 122 of dies 120. Thematerial of filling layer 130 can be epoxy, polymer, or the like. Aftercuring of filling layer 130, a grinding or etching process is applied toplanarize filling layer 130 so the top face of filling layer 130 isplanar with active surface 122 of dies 120.

Please refer to FIG. 1C, after the formation of filling layer 130 onceramic substrate 110, a dielectric layer 142 is formed on top offilling layer 130 and active surface 122 of dies 120. Dielectric layer142 is patterned according to metal pads 126 on dies 120 to formthru-holes 142 a. The material of dielectric layer 142 can be poly-Imide(PI), benzocyclobutene (BCB), porous dielectric material, stress buffermaterial, or the like. Patternization of dielectric layer 142 can beperformed by photo via, laser ablation, plasma etching, or the like.

Please continue to refer to FIG. 1C, filling layer 130 is used tosupport dielectric layer 142 so dielectric layer 142 can be formedplanarized on top of ceramic substrate 110 and dies 120 without anuneven surface. As a result, after dielectric layer 142 is formed onsurface 112 of ceramic substrate 110 and active surface 122 of die 120,dielectric layer 142 also fills the peripheral of dies 120, meaning thegap between dies 120. Therefore the bottom structure of dielectric layer142 can replace the structure of filling layer 130 covering entirelysurface 112 of ceramic substrate 110 and surrounding dies 120. Themethod of forming dielectric layer 142 includes first depositing a layerof dielectric layer 142 entirely over dies 120 and ceramic substrate110, then after curing, a grinding or etching process is performed toplanarize dielectric layer 142.

Please refer to FIG. 1D, after forming dielectric layer 142 andpatterning dielectric layer 142 to form thru-holes 142 a, a patternedwiring layer 144 is formed on top of dielectric layer 142 byphotolithography and sputtering, electroplating, or electro-lessplating. Wherein part of the conductive material from patterned wiringlayer 144 will be injected into thru-holes 142 a to form vias 142 b,copper (Cu) is used as the material for patterned wiring layer 144.Moreover, thru-holes 142 a can be pre-filled with a conductive materialsuch as a conductive glue to form vias 142 b. Therefore no matter if thethru-holes are filled with the conductive material from patterned wiringlayer 144 or pre-filled with a conductive material, patterned wiringlayer 144 is electrically connected to metal pads 126 of dies 120. It isto be noted that part of patterned wiring layer 144 extends to a regionoutside active surface 122 of dies 120. Dielectric layer 142 andpatterned wiring layer 144 form a thin-film circuit layer 140.

Please refer to FIG. 1E, after the formation of patterned wiring layer144, another dielectric layer 146 can be formed similarly to dielectriclayer 142 on top of dielectric layer 142 and patterned wiring layer 144.Dielectric layer 146 is also patterned to form thru-holes 146 a, whereasthru-holes 146 a correspond to bonding pads 144 a of patterned wiringlayer 144.

Please refer to FIG. 1F, after the formation and patternization ofdielectric layer 146 to form thru-holes 146 a, a patterned wiring layer148 can be formed on dielectric layer 146 in a similar way as patternedwiring layer 144. Wherein part of the conductive material from patternedwiring layer 148 will be injected into thru-hole 146 a forming a via 146b. By the same token, patterned wiring layer 148 is electricallyconnected to patterned wiring layer 144 by vias 146 b, and furtherelectrically connected to metal pads 126 of die 120 by vias 142 b ofthru-hole 142 a. Therefore, thin-film circuit layer 140 furthercomprises dielectric layer 146, a plurality of vias 146 b, and patternedwiring layer 148.

Please continue to refer to FIG. 1F, in order to redistribute all metalpads 126 of dies 120 on ceramic substrate 110, the number of patternedwiring layers (144, 148 . . . ) and dielectric layers (142, 146 . . . )for electrical insulation may be increased. All patterned wiring layers(144, 148 . . . ) are electrically connected by vias (146 b . . . ) ofthru-holes (146 a . . . ). However if only the first patterned wiringlayer 144 is required to entirely redistribute metal pads 126 of dies120 on ceramic substrate 110, extra dielectric layers (146 . . . ) andpatterned wiring layers (148 . . . ) will no longer be required in thestructure. In other words, thin-film circuit layer 140 comprises atleast one dielectric layer 142, one patterned wiring layer 144, and aplurality of vias 142 b. Wherein patterned wiring layer (144, 148 . . .) and vias (142 b, 146 b . . . ) of thin-film circuit layer 140 form anexternal circuitry of thin-film circuit layer 140.

Please refer to FIG. 1G, after the formation of patterned wiring layer148, a patterned passivation layer 150 is formed on top of dielectriclayer 146 and patterned wiring layer 148. Patterned passivation layer150 is used to protect patterned wiring layer 148 and expose theplurality of bonding pads 148 a of patterned wiring layer 148, whereassome of bonding pads 148 a are in a region outside active surface 122 ofdies 120. As previously mentioned, the redistribution of metal pads 126on ceramic substrate 110 requires multiple layers of patterned wiringlayers (144, 148 . . . ) and a patterned passivation layer 150 formed onthe very top, which is furthest away from ceramic substrate 110.However, if only patterned wiring layer 144 is required to redistributemetal pads 126 of dies 120 on ceramic substrate 110, patternedpassivation layer 150 will be formed directly on patterned wiring layer144. The material of passivation layer 150 can be anti-solder insulatingcoating or other insulating material.

Please refer to FIG. 1H, after the formation of patterned passivationlayer 150, a bonding point 160 can be placed on bonding pads 148 aserving as an interface for electrically connecting die 120 to theexternal circuitry. Wherein bonding point 160 illustrated in FIG. 1H isa ball but it is not limited to any formation, which might include abump, pin, or the like. Ball connector maybe solder ball, and bumpconnector maybe solder bump, gold bump, or the like.

Please refer to FIG. 11, after the formation of bonding points 160 onbonding pads 148 a, a singularization process of packaged die 120 bymechanical or laser cutting is performed along the dotted line asindicated in the diagram. Afterwards, the chip package structure of thedie is completed.

According to the above, the first embodiment of the present invention isa chip package structure with a ceramic substrate and a plurality ofdies on it. The external circuitry of the thin-film circuit layer allowsthe metal pads of the die to fan out. By forming bonding padscorresponding to the metal pads of the dies such as solders balls,bumps, or pins as the signal input terminals, the distance of the signalpath is effectively decreased. As a result, signal delay and attenuationare reduced to increase performance of the die.

Ceramic material possesses advantageous properties such as highstructural rigidity, high anti-corrosive properties, high density, andhigh thermal conductivity. Coefficient of thermal expansion (CTE) ofaluminum oxide ceramic material is comparable to that ofiron-cobalt-nickel alloy. The present invention specifically applies theuse of ceramic material due to its high structural rigidity, highanti-corrosive properties, high density, and high thermal conductivity,which means that the package structure can be used in unfavorableenvironments such as high-corrosiveness, high humidity, or hightemperature environment. The high CTE of ceramic material will help thedies to dissipate heat for improved performance. Furthermore, thefabrication of ceramic-BGA (CBGA) substrate is already well know in theart, therefore current manufacturing machines can be easily adapted tomanufacture the ceramic substrate of the present invention for lowercost.

The second embodiment of the present invention differs from the firstembodiment by having inwardly protruded areas in the ceramic substrate.This area is for placement of the die with the backside of the dieadhered to the bottom of the area so the overall thickness of the chippackage structure is reduced. FIGS. 2A to 2C are schematic diagrams ofthe sectional view of the second embodiment illustrating the fabricationof the structure.

Please refer to FIG. 2A, a ceramic substrate 210 with a surface 212 isprovided. In FIG. 2B, a plurality of inwardly protruded areas 214 isformed on ceramic substrate 210 by machining such as milling. The depthof each inwardly protruded area 214 is approximately equal to thethickness of die 220, therefore the outline and depth of inwardlyprotruded areas 214 will be the same as dies 220 in FIG. 2C. In FIG. 2C,backside 224 of dies 220 is adhered to the bottom of inwardly protrudedareas 214 so dies 220 are inlayed in inwardly protruded areas 214.Active surface 222 of die 220 is exposed along surface 212 or ceramicsubstrate 210.

An alternative method of forming inwardly protruded areas 214 in ceramicsubstrate 210 in FIG. 2B is to use two green sheets 210 a and 210 b thatare not sintered, as illustrated in FIG. 2D. Green sheet 210 a hasopenings 214 a and by overlapping the two green sheets 210 a, 210 b andsintering them at a high temperature, opening 214 a in green sheet 210 awill form inwardly protruded areas 214 on green sheet 210 b as seenbefore in FIG. 2B, illustrated in FIG. 2E. The thickness of green sheet210 a is approximately equal to that of die 220 so the depth of inwardlyprotruded areas 214 is approximately equal to the thickness of die 220.

Furthermore, in FIGS. 2D and 2E, the two green sheets 210 a and 210 bprovided can be already sintered before putting together. Openings 214 acan be formed before or after sintering green sheet 210 a. Following,the two green sheet 210 a, 210 b are overlapped to form inwardlyprotruded openings 214 in ceramic substrate 210.

The structure of the second embodiment of the present invention afterFIG. 2C will follow FIGS. 1C to 1I from the first embodiment of thepresent invention, therefore it will not be repeated.

The second embodiment of the present invention is a ceramic substratewith a plurality of inwardly protruded areas for inlaying dies byadhering the backside of the dies to the bottom of the inwardlyprotruded areas and exposing the active surface of the dies. A thin-filmcircuit layer is formed on top of the dies and the ceramic substrate tofan out the metal pads of the dies by using the external circuitry ofthe thin-film circuit layer. Due to the inlay of the dies in the ceramicsubstrate, thinning of the thickness of the chip package structure iseffectively achieved and the surface of the ceramic substrate providesenough planarity and support for the formation of the thin-film circuitlayer.

The third embodiment of the present invention differs from the secondembodiment of the present invention by using an integrated ceramicsubstrate with at least one ceramic layer and one heat conducting layer.FIGS. 3A to 3C are schematic diagrams of the sectional view of the thirdembodiment illustrating the fabrication of the structure.

Please refer to FIG. 3A, an integrated ceramic substrate 310 consists ofa ceramic layer 310 a with multiple openings 314 a and a heat conductinglayer 310 b, wherein the material of heat conducting layer 310 b maybemetal. In FIG. 3B, ceramic layer 310 a is placed overlapping heatconducting layer 310 b so openings 314 a of ceramic layer 310 a forminwardly protruded areas 314. Following in FIG. 3C, backside 324 of die320 is adhered to the bottom of inwardly protruded areas 314 so dies 320are inlayed in ceramic substrate 310 with active surface 322 of die 320exposed along surface 312 of ceramic board 310.

The following presents two ways of forming integrated ceramic substrate310 with inwardly protruded areas 314 as shown in FIG. 3B. In FIG. 3A, anon-sintered ceramic layer (green sheet) 310 a with openings 314 a isprovided, and in FIG. 3B, the non-sintered ceramic layer 310 a isoverlapped on heat conductive layer 310 b so openings 314 a of ceramiclayer 310 a can form inwardly protruded areas 314 on the surface of heatconducting layer 310 b. Afterwards, integrated ceramic substrate 310with ceramic layer 310 a and heat conducting layer 310 b are sintered ata temperature above 1000° C. Therefore the material of heat conductinglayer 310 b must have a higher melting temperature than the temperatureused for sintering the green sheet.

The alternative method is using an already-sintered ceramic layer 310 awith openings 314 a. The already-sintered ceramic substrate layer 310 ais overlapped on heat conducting layer 310 b so openings 314 a ofceramic layer 310 a can form inwardly protruded areas 314. The thicknessof ceramic layer 310 a is approximately equal to that of die 320 so thedepth of openings 314 a is also approximately equal to the thickness ofdie 320.

The structure of the third embodiment of the present invention afterFIG. 3C will follow FIGS. 1C to 1I from the first embodiment of thepresent invention, therefore it will not be repeated.

The third embodiment of the present invention is an integrated ceramicsubstrate with a ceramic layer with a plurality of openings and a heatconducting layer. The openings in the ceramic layer will form inwardlyprotruded areas on the integrated ceramic substrate. Backside of the dieadheres to the bottom of the inwardly protruded areas so the dies areinlayed in the inwardly protruded areas exposing the active surface ofthe dies. This integrated ceramic substrate can efficiently dissipateheat from the dies to the outside because the bottom of the inwardlyprotruded area is the surface of the heat conducting material. Thesurface of the ceramic substrate provides enough planarity and supportfor the formation of the thin-film circuit layer.

The fourth embodiment of the present invention is slightly differentfrom the first three embodiments. FIGS. 4A to 4E are schematic diagramsof the sectional view of the fourth embodiment illustrating thefabrication of the structure.

Please refer to FIG. 4A, a ceramic substrate 410 with a first surface412 and a plurality of dies 420 are provided. The dies 420 have anactive surface 422, a backside 424, and a plurality of metal pads 426located on active surface 422. The fourth embodiment of the presentinvention differs from the third embodiment of the present invention byplacing active surface 422 of die 420 downwards facing first surface 412of ceramic substrate 410.

Please refer to FIG. 4B, a filling layer 430 is formed on top of firstsurface 412 of ceramic substrate 410 after active surface 422 of die 420is adhered to first surface 412 of ceramic substrate 410. Filling layer430 covers entirely first surface 412 of ceramic substrate 410 andsurrounds dies 420. The material of filling layer 430 maybe an oxide,epoxy, or the like.

Please refer to FIG. 4C, after the formation of filling layer 430, aplanarization process such as grinding is performed to planarize fillinglayer 430 and backside 424 of dies 420. Although the thickness of theactive devices and wiring (not shown) on active surface 422 of die 420is much less than that of dies 420, the thickness of die 420 should notbe too small because cracks or damage to the die will occur duringmachine handling. However the present invention directly adheres activesurface 422 of dies 420 to first surface 412 of ceramic substrate 410without further machine handling. Afterwards a grinding process isperformed on backside 424 of dies 420 to reduce the thickness of dies420. As a result, dies 420 are ground to a very small thickness allowingthe final chip package structure to be much thinner.

Please refer to FIG. 4D, after the planarization of filling layer 430and dies 420, a second ceramic substrate 440 with a second surface 442is adhered to filling layer 430 and dies 420 creating a sandwich effectwith filling layer 430 and dies 420 in between two ceramic substrates410 and 440.

Please refer to FIG. 4E, after the adhesion of second ceramic substrate440, a grinding or the like process is performed to thin the backside ofceramic substrate 410 to achieve a thickness of about 2 microns to 200microns, usually about 20 microns. First ceramic substrate 410 is usedto provide a planar surface for dies 420 to adhere to and to serve as aninsulating layer. Therefore ceramic substrate 410 can be replaced bysubstrate made of glass or other organic material.

Please refer to FIG. 4F, after the thinning of first ceramic substrate410, a plurality of first thru-holes 410 a are formed on first ceramicsubstrate 410 for exposing metal pads 426 of active surface 422 of die420. First thru-holes 410 a can be formed by machine drilling, laser,plasma etching, or similar methods.

Please refer to FIG. 4G, a first patterned wiring layer 450 is formed onfirst ceramic substrate 410. Using the same method disclosed in thefirst embodiment of the present invention, first vias 410 b in firstthru-holes 410 a are formed by either filling first thru-holes 410 awith part of the conductive material from patterned wiring layer 450 orpre-filling first thru-holes 410 a with a conductive material before theformation of patterned wiring layer 450. A part of patterned wiringlayer 450 will extend to a region outside active surface 422 of die 420.

Please refer to FIG. 4H, a dielectric layer 462 is formed on firstceramic substrate 410 and first patterned wiring layer 450. Whereindielectric layer 462 is patterned to form a plurality of secondthru-holes 462 a, which correspond to bonding pad 450 a of patternedwiring layer 450.

Please refer to FIG. 41, a second patterned wiring layer 464 is formedon dielectric layer 462. Using the same method as above, second vias 462b in second thru-holes 462 a can be formed by either filling secondthru-holes 462 a with part of the conductive material from patternedwiring layer or pre-fill second thru-holes 462 a with a conductivematerial before the formation of patterned wiring layer 464. Similarly,in order to redistribute metal pads 426 of dies 420 on second ceramicsubstrate 440, dielectric layer (462 . . . ), second vias (462 a . . .), and second patterned wiring layer (464 . . . ) can be repeatedlyformed on dies 420 and second ceramic substrate 440. Wherein firstceramic substrate 410, first patterned wiring layer 450, dielectriclayer 462 . . . , and second patterned wiring layer 464 . . . formthin-film circuit layer 460. First vias 410 b, first patterned wiringlayer 450, second vias 462 b . . . , and second patterned wiring layer464 form the external circuitry of thin-film circuit layer 460.

The structure of the fourth embodiment of the present invention afterFIG. 4I will follow FIGS. 1G to 1I from the first embodiment of thepresent invention, therefore it will not be repeated.

The fourth embodiment of the present invention is a ceramic substratewith the active surface of the dies directly adhered to the surface ofthe first ceramic substrate. A filling layer is formed over the dies andthe ceramic substrate followed by a planarization and thinning process.Afterwards, a second ceramic substrate is adhered to the die and thefilling layer. A thinning process of the first ceramic substrate isperformed and a plurality of thru-holes filled with conductive materialare formed on the first ceramic substrate. Finally a patterned wiringlayer is formed on the first ceramic substrate allowing the externalcircuitry of the thin-film circuit layer to extend to a region outsidethe active surface of the die to help fan out the metal pads of the die.

The advantage of this structure is increased surface stability andaccuracy because the active surface of the dies are first adhered to thesurface of the first ceramic substrate. The thickness of the die can bevery small for reducing the overall thickness of the chip packagebecause no machine handling of dies is required.

The fifth embodiment of the present invention takes the first half ofthe fabrication process from the fourth embodiment of the presentinvention and combines with the second half of the fabrication processfrom the first embodiment of the present invention. FIGS. 5A to 5E areschematic diagrams of the sectional view illustrating the fabrication ofthe structure.

Please refer to FIG. 5A, an active surface 522 of dies 520 is adhered toa first surface 512 of a first ceramic substrate 510. In FIG. 5B, afilling layer 530 is formed on top of dies 520 and first ceramicsubstrate 510 covering dies 520. In FIG. 5C, a planarization andthinning process of dies 520 and filling layer 530 is performed toplanarize backside 524 of dies 520 and filling layer 530. In FIG. 5D, asecond ceramic substrate 540 is formed on top of dies 520 and fillinglayer 530 so backside 524 of dies 520 adheres to second ceramicsubstrate 540. By removing filling layer 530 and first ceramic substrate510, the metal pads on active surface 522 of dies 520 are exposed. Firstceramic substrate 510 is used to supply a planarized surface (firstsurface 512), and will be removed in later stages of the fabricationprocess. Therefore first ceramic substrate 510 can be replaced bysubstrates of other materials such as glass, metal, silicon, or otherorganic material.

The structure of the fifth embodiment of the present invention afterFIG. 5E will follow FIGS. 1B to 1I of the first embodiment of thepresent invention, therefore it will not be repeated.

The fifth embodiment of the present invention is a ceramic substratewith the active surface of the die adhered to the surface of the firstceramic substrate for allowing high surface stability and accuracy. As aresult, it eliminates the need of machine handling of the dies toachieve a very small thickness of the die for reducing the overallthickness of the chip package.

Furthermore, please refer to FIG. 6, it illustrates the schematicdiagram of the sectional view of the chip package structure 600 of thepresent invention for a single die 620. Die 620 is placed on ceramicsubstrate 610, and a thin-film circuit layer 640 is formed on top ofdies 620 and ceramic substrate 610. External circuitry 642 of thin-filmcircuit layer 640 has at least has one patterned wiring layer 642 a anda plurality of vias 642 b. The thickness of the inner traces inside die620 is usually under 1 micron, but because the high amount of tracescollocated together so RC delay is relatively high and the power/groundbus requires a large area. As a result, the area of die 620 is notenough to accommodate the power/ground bus. Therefore the chip packagestructure 600 uses thin-film circuit layer 640 and external circuitry642 with wider, thicker, and longer traces to alleviate the problem.These traces act an interface for transmitting signals for the internalcircuitry of die 620 or the power/ground bus of die 620. This willimprove the performance of die 620.

Please refer to FIG. 8, it illustrates a magnified view of the sectionalview of the chip package structure of the present invention. Activesurface 622 of die 620 has a plurality of active devices 628 a, 628 b,and an internal circuitry 624. The internal circuitry 624 forms aplurality of metal pads 626 on the surface of die 620. Therefore signalsare transmitted from active devices 628 a to external circuitry 642 viainternal circuitry 624 of die 620, and from external circuitry 642 backto another active device 628 b via internal circuitry 624. The traces ofexternal circuitry 642 are wider, longer, and thicker than that ofinternal circuitry 624 for providing an improved transmission path.

Please continue to refer to FIG. 6, external circuitry 642 furthercomprises at least one passive device 644 including a capacitor, aninductor, a resistor, a wave-guide, a filter, a micro electronicmechanical sensor (MEMS), or the like. Passive device 644 can be locatedon a single layer of patterned wiring layer 642 a or between two layersof patterned wiring layers 642 a. In FIGS. 9A, 9B, passive device 644can be formed by printing or other method on two bonding points onpatterned wiring layer 642 a when forming thin-film layer 640. In FIG.10A, a comb-shape passive device 644 (such as a comb capacitor) isformed directly on a single patterned wiring layer. In FIG. 10B, passivedevice 644 (such as a capacitor) is formed between two layers ofpatterned wiring layers 642 a with an insulating material 646 inbetween. Wherein the original dielectric layer (not shown) can replaceinsulating material 646. In FIG. 11A, passive device 644 (such as aninductor) is formed by making a single layer of patterned wiring layer642 a into a circular or square (not shown) spiral. In FIG. 11B,column-shape passive device 644 (such as an inductor) is formed by usingtwo layers of patterned wiring layers 642 a and a plurality of vias 642b to surround an insulating material 646 forming a column. In FIG. 11C,circular-shaped passive device 644 (such as an inductor) is formed byusing slanted traces from two layers of patterned wiring layers and aplurality of vias 642 b to surround an insulating material 646 in acircular manner forming a pie. The above structures allow the originalexternally welded passive devices to be integrated into the inside ofthe chip package structure.

FIG. 6 illustrates a chip package structure 600 for a single die 620 butFIG. 7 illustrates a chip package structure 700 for a plurality of dies.Chip package structure 700 in FIG. 7 differs from chip package structure600 in FIG. 6 by having a die module 720, which comprises at least oneor more dies such as die 720 a, 720 b. Die 720 a, 720 b are electricallyconnected by the external circuitry of the thin-film circuit layer. Thefunction of die 720 a, 720 b can be the same or different and can beintegrated together by external circuitry 742 to form a multi-die module(MCM) by packaging same or different dies into one chip packagestructure. When multiple dies are packaged into the same chip packagestructure, singulation process is performed on the determined number ofdies.

Following the above, the present invention provides a chip packagingmethod by adhering a die to a ceramic substrate or to an inwardlyprotruded area of a ceramic substrate, and forming a thin-film circuitlayer with bonding pads and points above the die and ceramic substrate.This structure can fan out the metal pads on the die to achieve a thinchip package structure with high pin count.

Comparing to the BGA or PGA package technique used in the prior art, thechip package of the present invention is performed directly on the dieand the ceramic substrate for fanning out the metal pads on the die. Itdoes not require flip chip or wire bonding to connect the die to themicro-spaced contact points of a package substrate or carrier. Thepresent invention can reduce cost because the package substrate withmicro-spaced contacts is very expensive. Moreover the signaltransmission path of the present invention is reduced to lessen theeffect of signal delay and attenuation, which improves the performanceof the die.

Furthermore, the present invention uses ceramic substrate with highstructural rigidity, high anti-corrosive properties, high density, andhigh thermal conductivity, which means that the package structure can beused in unfavorable environments such as high-corrosive, high humidity,or high temperature environment. The high CTE of ceramic material willhelp the die dissipate heat to improve performance. Furthermore,ceramic-BGA (CBGA) is already well know in the skilled of the art, whichcan be adapted to current machines to manufacture the ceramic substrateof the present invention for lower cost.

Furthermore, the third embodiment of the present invention provides anintegrated substrate comprises a ceramic layer and a heat conductinglayer. A plurality of openings can be pre-formed on the ceramic layer soinwardly protruded areas are formed for inlaying the die when theceramic layer overlaps the heat conducting layer. The heat conductinglayer helps to dissipate heat to the outside from the die duringoperation, which will effectively increase performance.

The thin-film layer circuit of the present invention is used to transmitsignals between two main active devices inside the die, or used as apower/ground bus, or used to add in passive devices. Furthermore, thechip package structure of the present invention can accommodate one ormore dies with similar or different functions. The external circuitry ofthe thin-film circuit layer electrically connects the multiple diestogether and can be used in a MCM package. The chip package structure ofthe present invention adapts the MCM, the external circuitry of thethin-film circuit layer, the passive devices of the external circuitryto form a package that is “system in package”.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the structure of the presentinvention without departing from the scope or spirit of the invention.In view of the foregoing, it is intended that the present inventioncover modifications and variations of this invention provided they fallwithin the scope of the following claims and their equivalents.

What is claimed is:
 1. A chip package structure comprising: a preformedceramic substrate; a die positioned over the preformed ceramic substrateand having an active surface, a backside that is opposite to the activesurface, and a plurality of metal pads located on the active surface,wherein the backside of the die faces the preformed ceramic substrate;and a plurality of patterned lines positioned over the active surface ofthe dies and electrically connected to the metal pads, wherein thepatterned lines are constructed from at least a patterned wiring layer.2. The structure in claim 1, further comprising a dielectric layerpositioned over the die and over the preformed ceramic substrate, thepatterned wiring layer positioned over the dielectric layer, thedielectric layer having a plurality of via holes, and the patternedwiring layer electrically connected to the metal pads through the viaholes.
 3. The structure in claim 2, wherein a material of the dielectriclayer is selected from a group consisting of polyimide,benzocyclobutene, porous dielectric material, and stress buffermaterial.
 4. The structure in claim 1, wherein the die has a side wallthat is not covered by the preformed ceramic layer.
 5. The structure inclaim 1, further comprising a dielectric layer positioned over the dieand over the preformed ceramic substrate, the dielectric layerpositioned over the patterned wiring layer.
 6. The structure in claim 5,wherein a material of the dielectric layer is selected from a groupconsisting of polyimide, benzocyclobutene, porous dielectric material,and stress buffer material.
 7. The structure in claim 1, wherein thepatterned lines are constructed from a single patterned wiring layer. 8.The structure in claim 1, wherein the preformed ceramic substrate doesnot have conductive traces.
 9. The structure in claim 1, wherein thepreformed ceramic substrate comprises aluminum oxide.
 10. The structurein claim 1 further comprising a dielectric layer positioned over the dieand the preformed ceramic substrate, the patterned lines constructedfrom a plurality of patterned wiring layers, the dielectric layerpositioned between the adjacent patterned wiring layers, the dielectriclayer having a plurality of via holes, and the adjacent patterned wiringlayers electrically connected with each other through the via holes. 11.The structure in claim 10, wherein a material of the dielectric layer isselected from a group consisting of polyimide, benzocyclobutene, porousdielectric material, and stress buffer material.
 12. The structure inclaim 1 further comprising a polymer layer positioned over the preformedceramic layer, the die having a side wall enclosed by the polymer layer.13. The structure in claim 12, wherein a material of the polymer layeris epoxy.
 14. The structure in claim 1, wherein the preformed ceramicsubstrate has a surface facing the die, and the surface of the preformedceramic substrate has a horizontal area larger than that of the activesurface of the die.
 15. The structure in claim 1, wherein the patternedwiring layer comprises a plurality of exposed pads.
 16. The structure inclaim 1 further comprising a plurality of solder balls positioned on thepatterned wiring layer.